Architecture of RNA polymerase II and implications for the transcription mechanism
Architecture of RNA polymerase II and implications for the transcription mechanism
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DOI：
10.1126/science.288.5466.640
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发表时间：
2000-04-28
期刊：
影响因子：
56.9
通讯作者：
Kornberg, RD
中科院分区：
文献类型：
--
作者：
Cramer, P;Bushnell, DA;Kornberg, RD
一个10-亚基酵母RNA聚合酶II的骨干模型已来自X-射线衍射数据扩展到3埃的分辨率。所有10个亚基与相应的人类蛋白质表现出高度的同一性，并且10个亚基中的9个在三种真核RNA聚合酶I、II和III中是保守的。该模型的显著特征包括一对由亚基Rpb 1、Rpb 5和Rpb 9形成的钳口，它们似乎可以抓住活性中心下游的DNA。在靠近活性中心的DNA上，由Rpb 1、Rpb 2和Rpb 6形成的夹子可以被RNA锁定在闭合位置，从而解释了转录复合物的高度稳定性。活性中心下方的蛋白质复合物中的孔可以允许底物进入以进行聚合，并在校对和通过DNA中的暂停位点期间允许转录物离开。
A backbone model of a 10-subunit yeast RNA polymerase II has been derived from x-ray diffraction data extending to 3 angstroms resolution. All 10 subunits exhibit a high degree of identity with the corresponding human proteins, and 9 of the 10 subunits are conserved among the three eukaryotic RNA polymerases I, II, and III. Notable features of the model include a pair of jaws, formed by subunits Rpb1, Rpb5, and Rpb9, that appear to grip DNA downstream of the active center. A clamp on the DNA nearer the active center, formed by Rpb1, Rpb2, and Rpb6, may be Locked in the closed position by RNA, accounting for the great stability of transcribing complexes. A pore in the protein complex beneath the active center may allow entry of substrates for polymerization and exit of the transcript during proofreading and passage through pause sites in the DNA.